Hello to all!!! Egr vacuum headache!!!

[98CAMounty]

Hello guys im new to the forum but ive been using it as a great source since I bought my 5.0 mounty a year ago.

I tried to post this in troubleshooting but could not possibly because I have a new account? Anyway My 98 5.0 has an issue where I am havung constant vaccum at idle to egr which causes misfire, stumbing, and very rough idle. Its smog time and I need to figure this out quick as I get lean and misfire codes with egr hose from solenoid connected to egr. With the hose disconnected it runs great which has caused me to leave it disconnected while I fix the issue. I have installed new dpfe,solenoid, and have tested egr which holds pressure and is in working order. Anyone experienced anything like this? Thanks everyone glad to finally be a member!!!

 

[98CAMounty]

I have replaced crankshaft sensor , camshaft sensor,sychronizer,tps,dpfe,erg,solonoid,passenger exhaust manofold,pcv,have k and n cone, cleaned maf, smoke tested through brake booster line no vac leaks.

Any help would be appreciated guys?

 

[RangerX]

I can't help, other than I moved your thread into the 2nd Gen forum.
Should get more views here.

 

[1998Exp]

If you are convinced that the solenoid is not stuck open, the problem must be in its control. The solenoid has +12V at one end (the Light Blue/Orange wire) and is activated by the PCM grounding the other end (Brown/Pink control wire). I would suggest probing both wires with ignition on. Both wires should be at +12V, indicating that there is no current flowing through the solenoid. If you see +12V on the LB/Orange and close to 0V on the Brown/Pink, the solenoid is activated. It could be a failure of the PCM, but those are rare. More likely in that case the Brown/Pink control wire has a short to ground somewhere. If memory serves, the harness going in that direction is supported by a bracket, just next to the DPFE. I had a problem with that bracket cutting through the insulation and, in my case, grounding the IAT line. Worth a look. Good luck!

Hello guys im new to the forum but ive been using it as a great source since I bought my 5.0 mounty a year ago.

I tried to post this in troubleshooting but could not possibly because I have a new account? Anyway My 98 5.0 has an issue where I am havung constant vaccum at idle to egr which causes misfire, stumbing, and very rough idle. Its smog time and I need to figure this out quick as I get lean and misfire codes with egr hose from solenoid connected to egr. With the hose disconnected it runs great which has caused me to leave it disconnected while I fix the issue. I have installed new dpfe,solenoid, and have tested egr which holds pressure and is in working order. Anyone experienced anything like this? Thanks everyone glad to finally be a member!!!

 

[98CAMounty]

Thank you very much for the reply I will double check the wiring once again witg my multimeter. I even tested the solonoid hooked up to a vaccum guage while driving down the road and it did increase in vacuum pressure as I accelerated like its supposed to except instead of dropping down to zero psi at idle it would hover around 5 psi. Any chance timing could throw the PCM off and cause it to apply vac at idle ? I just thought that maybe I didnt get top dead center like I believe I did while installing my camshaft sensor and sychronizer. Thanks again!!!

 

[98CAMounty]

Oh and yes it is mounted to a bracket that connects to the intake manifold where the dpfe connects. I will report back any new findings. Thank you!!

 

[98CAMounty]

I kinda feel like an idiot but I had Solonoid vac hoses backwards problem solved... Thanks again!! Now on to my P0174 headache can this thing ever just be code free im starting to think its impossible...